Waterproof writing-paper for metallic styli.



SHINGO KUROKI, OF TOKYO, JAPAN, ASSIGNOR T0 KIMPI'ISU SEISHI KAISHA,L'JND., 0F TOKYO, JAN.

WATERPROOF WRITING-PAPER FOR METALLIC STYLE.

No Drawing.

To all whom it may concern:

Be it known that I, SHINGO KURoKI, a subject of the Emperor of Japan,residing at Tokyo, Japan, have invented certain new and usefulImprovements in Waterproof Writing-Paper for Metallic Styli, of whichthe following is a specification.

The present invention relates to Water proof writing paper; and itcomprehends, briefly, certain improvements, hereinafter fully described,in the preparation and treatment, from a chemical standpoint, of thepaper whereon the writingor marking is to be made, whereby such paper isrendered suitable for use in connection with metallic styli, the objectof the invention being to obviate defects ordinarily existing in theuusal methods of writing in which pens and ink or pencils are employed.

According to the invention, the paper to be used is subjected tosuccessive treatments with various chemical substances, with the resultthat a writing surface is formed thereon, on which marks made by a metalstylus are readily and permanently legible, such marks having a sharp orclear appearance which does not change color nor fade with time, norsmudge, and being of uniform color, as opposed to the diflerent degreesof shade or color appearing in ordinary ink or pencil writing. Also, thepaper itself maintains its original whiteness or color, and does notblacken with age.

In carrying out the invention, the sheets of paper to be used are firsttreated with a dilute solution of gum arabic, which is sprayed overeither or both surfaces thereof in any desired manner and with the aidof any suitable device. Powdered white clay, which maycontain a certainamount of fine, hard sand, is then scattered uniformly over the surfaceor surfaces of the paper; and after the surplus powder has been removed,a mixture composed of two parts, by volume, of castor oil one part ofbenzene and one part of vaselme, is applied thereto by means of aroller.

Oxidized zinc in powdered form may, if

desired, bemixed in equal quantities with the powdered clay, to sharpenor render more clear the marks written upon the paper; and half a part,by volume, of camphor oilmay be added to the above mixture of oils forthe purpose of eliminating the odor thereof.

Specification of Letters Patent.

Application tiled January 28, 1917. Serial No. 1449M Patented nllly It,III,

Writing is Perfore.m e sa y upon the paper and at the P etion of t ewriting operation, the letters, characters or other marks will be foundto have a clear and sharp appearance, and a uniform shade or color whichwill not fade out with age, as previously stated; while the paperlikewise tends to keep its original color.

These improved results are due primarily to the use both of the powderedwhite clay in place of the white paint more commonly utilized, and ofthe non-drying castor oil instead of the drying oil usuaily employed asa solvent for the paint, because of the fact that the white leadcontained in the paint has the tendency to oxidize in time and thus turnthe paper black, while a part of the drying oil gradually evaporates andthus lessens the smoothness of the writing surface, in consequencewhereof the movement of the stylus thereover is impeded. 0n the otherhand, the clay used according to the present invention does not becomeoxidized, and hence, does not tend to blacken the pa: per, and thecastor oil produces no such roughening or hardening of the writingsurface as'does the more generally used drying oil. It is important,however, to apply the powdered clay to the paper in the manner describedabove, before commencing with the oil treatment, for if the clay andoils were all mixed together and then applied by means of a roller orthe like to the paper, the clay might form separate deposits which wouldimpair. the smoothness of the writing surface. Furthermore, it isdesirable to. add both the benzene or other volatile oil and theVaseline mentioned above to the nondrying oil, since the latter, if usedalone, could not be satisfactorily applied as a coating for the writingsurface.

While it is essential to the invention to apply the powdered clay to thepaper before the latter is treated with the oil mixture, yet it ispossible to incorporate the powder in the pulp during the manufacture ofthe paper, instead of dustin it on a finished sheet of paper coated witgum arabic or other adhesive. Indeed, the incorporation of the powder inthe pulp is, in one respect at least, preferable to the firstmentionedmode of application, since paper so prepared may again be written onafter writing previously made thereon has been rubbed out by means of aneraser; whereas it is practically impossible to obtain shar dark writingon paper which 1s mere y coated with the powder, after having rubbed outthe previous writing, due to the fact that the passage of the eraserover the wr1ting surface necessarily has the effect of rea I moving someof the powder.

I claim as my invention- 1. The herein-described process ofmanufacturing writing paper for metallic styli,

which consists in treating paper material 7 with powdered clay;- andthereafter coating it with a' mixture composed of a nondrying oil, avolatile oil and vaseline.

2. The herein-described process of manuwith powdered clay; andthereafter coating it with a mixture composed of castor oil, a volatileoil and vaseline.

4. The herein-described process of manufacturing writing paper formetallic styli,

which consists in treating paper material with powdered clay; andthereafter coating it with a mixture composed of castor oil,

benzene and vaseline.

5. The herein-described process of manufacturing writing paper formetallic styli, which consists in treating paper material with powderedclay; and thereafter coating it with a], mixture composed of anon-drying oil, a volatile oil, vaseline and a deodorizing substance.

6. The herein-described process of manufacturing writing paper formetallic styli,

which consists in treating aper material with powdered clay; andtliereafter coating it with a mixture composed of a nondrying oil, avolatile oil, vaseline and camphor, oil'. g r

7. The herein-described process of manufacturing writing paper formetallic styli, which consists in treating paper material with a mixtureof powdered clay and zinc oxid; and thereafter coating it with a mixturecomposed of a non-drying oil, a volatile oil and vaseline.

8. The herein-described process of manufacturing writing paper formetallic styli, which consists in treating pa er material with a mixtureof powdered c ay and zinc oxid; and thereafter coating it with a mixturecomposed of a non-dryin oil, a volatile oil, vaseline and a doc orizingsubstance. 4

9. The herein-described process of manufacturing writing paper formetallic styli, which consists in treating paper material with a mixtureof powdered clay and zinc oxid; and thereafter coating it with a mixturecomposed of castor oil, benzene and vaseline.

10. The herein-described process of manufacturing writing paper formetallic styli, which consists in treating paper material with a mixtureof powdered clay and zinc oxid; and thereafter coating it with a mixturecomposed of castor oil, benzene, vaseline and a deodorizing substance.

In testimony whereof I aflix my signature in presence of two witnesses.

SHINGO KUROKI.

